Manufacture of gas



M. C. WHITAKER AND W. F. RITTMAN.-

MANUFACTURE OF GAS. APPLICATION FILED APR. 3. l9l4- Patefited Jan.6,1920.

UNITED STATES PATENT ormon MILTON C. WHITAKER AND WALTER F. RITTMAN, OFNEW YORK, N. Y., ASSIGNORS TO SYNTHETIC .HYDRO-CABBON COMPANY, OFPITTSBURGH, PENNSYLVANIA, A COR- PORATION OI DELAWARE.

Specification of Letters Patent.

Patented Jan. 6, 1920.

Application filed April 3, 1914. Serial No. 829,169.

To all whom it may concern:

Be it known that we, MILTON C. WHITA- KER and WALTER F. RITTMAN, bothcitizens of the United States, residing in the borough of Manhattan,city, county, and State shown in the accompanying drawing,in part of NewYork, respectively, have invented certain new and useful Improvements inthe Manufacture of Gas; and we do hereby declaim the following to be afull, clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertaiins to make and use thesame.

Our invention has for its purpose, pr1- marily increasing the yield ofgaseous illuminants obtained as a result of the cracking of hydrocarbonoils, and likewise involves increasing the total yield of fixed gasesfrom such oils, so that the resulting gaseous prod not has not only ahigher illuminating value, but a higher heating value as well.

The invention is based upon the discovery that by the cracking up of theoil into gases at reduced pressures, as hereinafter specified, theproportion of illuminants, that is to say, the unsaturated series ofhydrocarbons, such as ethylene, acetylene, etc., is increased to anextent which assumes commercial proportions when the pressure prevailingin the generating chamber or chambers is reduced to two-thirds of anatmosphere absolute and which, at still lower pressures is furtherrapidly augmented, reaching a maximum within the range of from 4 bs.pressure absolute downward. The increased yield in the unsaturatedseries of gaseous hydrocarbons by the practice of the invention, is alsoaccompanied, although to a lesser degree, by an increase in thesaturated series, such as methane, which accordingly add to the'heatingvalue of the final product. The invention is particularly applicable tooils of the petroleum type such as crude petroleum, shale oil, etc.

The process'is applicable not only to'the production of oil gas per 86,but also for brin ing water gas up 'tothe commercial standard of candlepower by combining the fixed gases due to the cracking up of the oilwith the original uncarbureted water gas; In fact, inasmuch as therequired candle power for carbureted water gas is directly dependentupon the percentage of illuminating constituents contained in the gasesresulting from the cracking up of the oil, the

amount of unsaturated hydrocarbons or illuoil, becomes a matter ofspecial importance in the manufacture of carbureted water gas.

For purposes of illustration, we have diagrammatically, anexemplification of a simple form of apparatus adapted to. thePlttOtlCBOf this invention, although it will be understood that theparticular apparatus shown is but typical of many others having the samecapabilities.

Referring to the drawing, A indicates a refractory-tube, which, in thisinstance, constitutes the gas generator, and which is capable ofwithstanding the vacuum incident to the practice of the invention. Inorder to controllably heat the retort any suitable means may be employedas, for example, a resistance-wire wrapping a, envelopin the gasgenerating tube A and suitably lIlSlllated therefrom. The gas generatorA and its electric heating element are incased in a protective coatingof magnesia, asbestos, or

other like refractory material, adapted to.

prevent excessive radiation of heat intothe surrounding atmosphere. Oneend of the resistance coil is connected to a binding post 6 and theother end through a conducting rod 0 to the binding post 03. From theseserves to support a small quantity of refractory filling material g (as,for instance, steel balls) located in the upper portion of thegenerating tube A and-within the same,-

the functions of this filling material being to afl'ord an efiicientspreading surface for the vaporization of the petroleum oil used. Theoil issupplied to the top of the gener ator A above the filling materialg, from a suitable source of supply, as, for instance,

the feeding cup or receptacle C. The pres- The generating tube A isfirst heated to the desired temperature for cracking the oil into fixedgases, by passing an. electric sure in the upper part of the feed cup orreceptacle is equalized with that in the tube A through an equalizingpipe t communicating at its lower end with the tube A, and at the otherend above the level of the oil in the feed cup 0. The generating tube Amay also be provided with a suitable gage sto indicate the pressureprevailing therein.

At the lower end, the generating tube A current ofappropriate wattagethrough the heating element a. When the generating tube A and thefillingmaterial 9 contained therein have attained the appropriate temperature,the oilfeed is opened and the'oil is permitted to enter the upper ,partof the generating tube A where it spreads over the filling material andis vaporized. In

the meantime, the vacuum pump G has been set in operation and draws theoil vapors downward into the cracking zone of, the

generating tube A, whereupon these vapors are immediately cracked upinto fixed gases and other products. These products, before opportunityis offered for polymerization or decomposition of the hydrocarbon gases,are withdrawn by the vacuumpump G from the crackin zone and their placeis taken by a quantity of oil vapor from the zone of filling material 9above. In this manner and continuously the hydrocarbon. gases, asquickly as they form, are withdrawn and after passing through thecondenser and receiver for the removal of the condensable vapors,solids, etc., are forwarded through the vacuum pump G to the gas holder.

As hereinbefore indicated, it is preferred to reduce the pressure asclose to zero as is appropriate to the cracking of the oil vapors underthe conditions of the operation. The degree of this temperature will, itis evident, depend in' part upon the length of time the vapors remain inthe cracking zone. In other words, if the cracking zone is of extremelyhigh temperature, the speed of travel of the gases should becorrespondingly expedited. For general purposes, however, and withapparatus of the kind and relative dimensions indicated in the drawing,a temperature of approximately 900 (3., as indicated by the pyrometer,is"

appropriate and sufiicient; it being understood, as indicated, thatshould thecracking zone be of greater heat intensity, it should be oflesser extent, so that the gaseous hydrocarbons formed may not suer-decomposition or polymerization by remaining too gaseoushydrocarbons, particularly in gaseous. illuminants of the unsaturatedhydrocarbon series begins to assume commercial importance at a reducedpressure equivalent to two-thirds of an atmosphere absolute. From thispoint, which may be regarded as the critical point in the process, theincrease in yield assumes rapidly increasing importance from thiscritical point, if the pressure is further reduced, and, in the rangebeginning with about 4 lbs. pressure absolute approximates a yield whichattains an increase of 100% in illuminants over the yield atatmospheric'pressure- We have further ascertained that the operation ofthe invention is not interfered with by passing through the generatortube, during the operation, hydrogen, or hydrocarbon gases such asmethane; nor is it interfered with by the presence ofcarbon monoxid (as,for iinstance, in the proportion in which carbon monoxid exists inuncarbureted water gas) unless the conditions of temperature and ofrelative concentration are such as to result in an unfavorableequilibrium in the sense in which that term is used in physicalchemistry.

What we claim is 1. The method of increasing the yield of an unsaturatedhydrocarbon series from a hydrocarbon oil of the petroleum type, which\comprises cracking the hydrocarbon when in,

four pounds to the square inch absolute,

substantially as described.

3. The method of increasing'the yield of gaseous hydrocarbons,particularly gaseous illuminants of the unsaturated hydrocarbon series,from a hydrocarbon oil of the petroleum type, which comprises vaporizingthe oil, cracking the oil vapors into fixed gases, continuouslysupplying the oil vapors to the cracking zone, and continuouslywithdrawing the products developed as a result of the cracking, at apressure less than two-thirds of an atmosphere absolute; substantiallyas described.

4. The method of increasing the yield of gaseous hydrocarbons,particularly gaseous illuminants ct the unsaturated hydrocarbon series,from hydrocarbon oil of the petroleum type, which comprises vaporizingthe oil, cracking the oil vapors into fixed gases, continuouslysupplying the oil vapors to the cracking zone, and continuouslywithdrawing the products developed as a result of the cracking, at apressure less than 4 lbs. to the square inch absolute; substantially asdescribed.

5. The method of cracking hydrocarbon oils of the petroleum type, whichconsists in vaporizing the oil, and thereafter heating the vapors to acracking temperature While under a pressure lower than two-thirds of anatmosphere absolute.

6. The method of cracking hydrocarbon oils of the petroleum type, whichconsists in vaporizing the oil in the upper portion of an uprightreaction chamber, thereafter subj ecting such vapors in a downwardlymoving column to a cracking temperature while under a pressuresubstantially below atmospheric pressure and of the order described, andwithdrawing the products of cracking from the bottom of such column.

7. The method of cracking hydrocarbon oils of the petroleum type, whichconsists in vaporizing the oil in the upper portion of an uprightreaction chamber, thereafter subjecting such vapors in a downwardlymoving column to a cracking temperature While under a pressure lowerthan two-thirds of an atmosphere absolute and withdrawing the productsof cracking from the bottom of such column.

8. The. method of cracking hyrocarbon oils, which comprises passing thesame into the upper portion of an upright heated unobstructed reactionchamber maintained at a cracking temperature, maintainin within saidchamber a pressure substantialTy below atmospheric pressure and of theorder described and withdrawing the products of cracking from the bottomof such chamber.

9. The method of cracking hyrocarbon oils of the petroleum type whichconsists in vaporizing the oil in the upper portion of an uprightreaction chamber, thereafter subjecting such vapors in a downwardlymoving column to a cracking temperature while under a pressuresubstantially below atmospheric pressure, withdrawing the products ofcracking from the bottom of such column, passing such products through acondenser and collecting the permanent ases. I

Tn testimony whereof we a X our signatures, in presence of twowitnesses.

MILTON C. WHITAKER. WALTER F. 'RTTTMAN. Witnesses:

C. B. SoHRoEDER, M. A. BIIL.

